Indexing turret



y 9 1957 R. l... M CLAIN 2,800,334

INDEXING TURRET Filed May 24, 1954 2 INVENTOR.

United States Patent INDEXING TURRET Richard L. McClain, Los Angeles, Calif., assignor, by mesne assignments, to Joseph A. Howard, Santa Clara, Calif.

Application May 24, 1954, Serial No. 431,752

2 Claims. (Cl. 279-51) This invention relates to means for supporting stock being fed through a tool-holding indexing turret or head and acted on by anyone of several tools held in .said head. The present invention is an improvement of the stock supporting means disclosed in Patent No. 2,596,482, issued May 13, 1952.

In said patent, three arms are arranged around the stock and provided with rollers that engage the stock and allow the same to rotate freely while worked on by said tools. Said roller-provided arms could support only round stock, it being necessary to string a sleeve or collar over non-round stock so the rollers may engage the cylindrical face of said sleeve and allow the stock to rotate, as shown in Fig. 7.

Recognizing the cumbersomeness of introducing such a sleeve when other than round stock is being handled by the head, it is an object of'the present invention to provide novel and improved means to support stock of diiferent polygonal character to enable free rotation thereof while worked on by the different tools of an indexing turret or head.

Another object of the invention is to provide means that, without change, can support both cylindrical and polygonal stock of the same outer diametral size.

The invention also has for its objects to provide such means that are positive in operation, convenient in use, easily installed in a working position and easily disconnected therefrom, economical of manufacture, relatively simple, and of general superiority and serviceability.

The invention also comprises novel details of construction and novel combinations and arrangements of parts, which will more fully appear in the course of the following description. However, the drawing merely shows and the following description merely describes, one embodiment of the present invention, which is given by way of illustration or example only.

In the drawing, like reference characters designate similar parts in the several views.

Figs. 1 is a cross-sectional View of a tool-indexing turret embodying the present improvements.

Fig. 2 is an enlarged side elevational view, in quarter section, of the improved stock supporting means of the present invention.

The tool-indexing device that is illustrated comprises a mounting bracket 5 provided with a hub 6 in which bearings 7 are provided, stock supporting means 8 extending through and supported rotationally by said bearings 7 and constituting a boss for a turret 9 which mounts a plurality of radially disposed tools 10, and operating means 11 to index the turret and simultaneously shift stop means 12. Said turret 9 is provided on one side of bracket 5 and stop means 12 is provided on the other side, the latter locating the tools relative to the forward end of a length of stock 13 extending axially through the stock supporting means.

The above described device is adapted to be mounted on a longitudinally movable carriage 14 of a lathe or like machine and the stock 13 may be fed toward and arrested in its feed movement by tail stock 15 of such machine. The stop means 12 is adapted to be operatively associated with the head stock of the machine, as shown in Fig. 1 of Patent No. 2,596,482.

The novelty of the present invention resides in the stock supporting means 8 of the tool-indexing device above described, the same holding stock 13 steady while being acted on by tools 10. In the present instance, said means 8 forms a boss for turret 9.

The stock supporting means 8 that is illustrated comprises, generally, a hub 16, a spring collet 17 extending axially through said hub, a radial bearing 18 carried by the hub and engaged by the spring end of collet 17, a thrust bearing 19 around the opposite end of said collet and disposed in end abutting engagement with hub 16, and an adjusting nut 20 carried by said opposite end of the collet and engaged with said thrust hearing.

The hub 16 comprises a cylindrical extension 21 that is mounted in bearings 7 of the indexing device, and a flange 22 by means of which said hub is aflixed to the index turret 9 as by screws 23. Said flange 22 is formed to have a recess 24 in which outer race 25 of bearing 18 is tightly fitted. Consequently, the inner race 26 of said bearing is rotational relative to hub 16. The end of extension 21 that is remote from flange 22 is shown as externally threaded at 27 for engagement by locking nuts 28 that mount stop means 12 on hub 16.

The collet 17 extends through the longitudinal bore 29 of hub 16 and, at the flange end of said hub, said collet is provided with jaws 30 which are of the spring type by reason of longitudinal slits 31. Where the outer peripheral face of the collet engages the inner race 26 of bearing 18, the same is conically flared, as at 32. Consequently, endwise shift of the collet, in a direction toward the threaded end of hub 16, will cause the spring jaws to be inwardly flexed as said conical face is axially moved relative to said inner bearing race. Therefore, stock 13, in the bore 33 of said collet, is gripped by the inwardly flexed jaws 31.

The two bearings 18 and 19 are conventional, each for its respective type. How radial bearing 18 is placed appears clear from the foregoing, Thrust bearing 19 has one plate 34 thereof in end abutment with hub extension 21, said plate and plate 35 on the opposite side of the bearing being fitted over the reduced end 36 of collet 17.

The adjusting nut 20 is engaged with threads 37 formed on said collet end 36 and may be advanced on said threads to draw the collet in the direction to inwardly flex or tighten the jaws 30 or turned back on said threads to loosen the same. In practice, nut 20 is taken up to such a degree that stock 13, while being firmly gripped by the collet jaws, is enabled to be projected endwise into engagement with tail stock 15. After such adjustment has been made, a clamp screw 38 on nut 20 is tightened to close the slit provided in said nut, as shown.

It will be clear from the foregoing that collet 17 is freely rotatable in hub 16, being supported at one end by radial bearing 18 and at the other end by thrust hearing 19.

Providing the stock is sized for the size of the collet, it is immaterial what is the cross-sectional form of said stock.

While the foregoing has illustrated and described what is now contemplated to be the best mode of carrying out the invention, the construction is, of course, subject to modification without departing from the spirit and scope of the invention. It is, therefore, not desired to restrict the invention to the particular form of construction illustrated and described, but to cover all modifications that may fall within the scope of the appended claims.

1. In an indexing turret, a hub affixed to said turret and provided at one end with a radial bearing having a rotatable inner race and at the other end with a thrust bearing, said hub having an axial bore, a spring collet disposed in said bore and having stock-gripping spring jaws at one end, means comprising threads on theend of said collet and an adjusting nut engaged with said threads and carried by said collet and engaged with the thrust bearing to press said thrust bearing against the end of the hub remote from the radial bearing and thereby move said collet axially in said hub, and conically flared means on the outer face of said collet jaws engaged with the inner race of the radial bearing to flex said collet jaws into gripping engagement with stock extending axially through said collet when said collet is moved axially upon tightening of said nut.

2. In an indexing turret, a hub affixed to said turret, said hub being provided at one inner end with a radial bearing having a rotatable inner race and at the other end with a thrust bearing, said hub having an axial bore, a spring collet disposed in said bore, said collett having a conical lower end positioned within said inner race and formed with slots to provide spring jaws, the upper end of said collet being formed with external threads, an adjusting nut engaging said threads and abutting the thrust bearing to press said thrust bearing against the end of the hub remote from the radial bearing to thereby move said collett axially in said hub, whereby the conically flared jawed end of the collett engages the inner race of the radial bearing and is flexed into gripping engagement with stock extending axially through said collet for gripping the latter.

References Cited in the file of this patent UNITED STATES PATENTS 952,149 Smith et a1 Mar. 15, 1910 2,369,330 Wilson Feb. 13, 1945 20 2,401,071 Hillberg May 28, 1946 2,596,482 Howard May 13, 1952 

